Use earlier version of Tycho when building with JDK7
diff --git a/pom.xml b/pom.xml
index 59bd4da..861a060 100644
--- a/pom.xml
+++ b/pom.xml
@@ -380,5 +380,14 @@
         </plugins>
       </build>
     </profile>
+    <profile>
+      <id>jdk7</id>
+      <activation>
+        <jdk>1.7</jdk>
+      </activation>
+      <properties>
+        <tycho-version>0.24.0</tycho-version>
+      </properties>
+    </profile>
   </profiles>
 </project>